Emergency-brake for elevators.



P. G. SLOWE. EMBRGENCY BBAKBFOR ELEVATORS.

APPLIOATION FILBD JULY 23, 1906.

Patented Mar. 26, 1912.

2 SEEETS-BEEET 1.

P. C. SLOWE.

EMERGBNCY BRAKE FOR ELEVATORS.

` APPLIOATION PILED JULY 23, 1908.

Patented Mar. 26. 1912.

2 BEEBTB-SHEBT 2.

EOLUMBM PLANOORAPH CO; WASHINGTON. I?. C.

PRESTON c. SLOWE, or PHILADELPI-IA, ?ENNSYLVANAIAQ EMERGENCY-BRAKE Fon ELEvAroRs.

Specfication of Letters Patents.

Patented Mar. 26 1912.

Application filed July 23, 1906. Serial No. 3273436.

T 0 all whom it may concc'm Be it known that I, PRESTON C. Snown, a citizen of the United States, residing at. Philadelphia, in the County of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Emergency-Brakes for Elevators, of which the following is a specification.

This invention relates to emergency brakes for elevator cars, and one of the principal objects of the same is to provide simple, reliable and etlicent means for stopping an elevator car at any point whenever the cable breaks or whenever the hoisting mechanism becomes inoperative.

Another object is to provide a simple and reliable device for the purpose indicated which can loe rendered instantly available whenever an emergency arises requiring the elevator to be thrown out of action in case of accident.

Still another object of the invention is to simplify the Construction and reduce the number ot' parts in devices ot' the cha ractcr referred to with a View to rendering the same more etlicient in use and less liable to get out of order.

The foregoing objects and advantages are attained by means of the construction illustrated in the aceompanying drawing, in which- Figure 1 is a side elevation of one member of an emergency brake made in accordance with the present invention, connected under neath the floor of an clevator car: Fig. 2 is a horizontal View shown partly in section and partly in full lines of one member of my improved emergency brake, and Fig. 3 is a front elevation of both members of the brake, and showing the floor of the cariin section.

Referring to thedrawing for a more particular description of the invention, the numeral 1 designates the floor of the elevator car, and 2 is the post or brake rail. It will be understood that there are two posts or brake rails, one on each side of the elevator shaft, Secured to the side walls of the shaft casing, as shown more particularly in Fig. 3. Since the brake mechanism is duplicated and of like Construction on each side, the description of one member of the deviee will be sufficient for the purpose of this description.

Secured rigidly under the floor 1 of the elevator car is a bracket or hanger 3, said braeket being in the 'form of a box or casing, and projecting downwardly froni the under surface of the floor 1. Journaled in the hangers 3 at opposite sides ot' the car, is a transverse shat't- 4-, and fixed upon this sha ft within the hanger is an eccentrically disposed brake lever cousisting' of a hub (S, fixed to the shatt 4, a web 7, and an eccentric brake Shoe 8, the latter being preferably faced with a suitable frictional material or surface 9. An op positely disposed brake lever is fixed to a stub shaft 4 journaled in the hanger 3, said lever also comprising a hub ti a web 7 and an eccentric brake Shoe S provided with a frictional surface 9% Fixed to the transverse shaft 4 and to the stub sha'ft 4 outside the hanger 3, are two bell crank levers 10, each of said levers including a hub 10 and an arn 4, and the inner ends of these arms are pivotally connected by a link 13-. The lower end portion of each of the levers 10 is provided with a perforation 11, and a spring 12 is connected at its ends with said perfcrated ends of levers 10, as clearly shown .in Fig. 1.

Projccting upward from the hub 10 ol? one bell-crank lever 10, is a stop lug 14, provided with a vertical face 15, and a curved surface 16. A lever 17, pivoted at 18 to the hanger 3 carries a roller 19 at its outer end which engages the stop lug 14 and normally holds the brake shoes 8, 8, out of contact with the post or rail 2. At the opposite end of the lever 17, a push button 20, passing through the floor of the car bears upon said lever, and may be instantly operated by a person in the car to release the roller 19 from the stop lug 14 to permit the spring 12 to draw the brake levers toward each other and apply the brake shoes 8, 8 to the post or rail 2, as will be understood. In order to disengage the brake shoes from the post or rail 2, any suitable device may be used, and as shown the shaft 4 is provided with a fixed jack ring 21, provided with an annular series of sockets 92 to acconmodate a jack bar, (not shown) for rotating the shat't 4 against the tension of the spring 12. The operation of the emergency brake may be described as follows: The parts being in the positions indicated in Fig. 1, should an emergency arise requiring the use of the brake mechanism, the push button 20 is stepped upon by the elevator conductor, and the stop lug 14 is released from the roller 19 and the spring 12 draws the brake levers together, the brake shoes then engaging the post or rail 2 on opposite sides of the car. Owing to the eccentrc disposition of the brake levers the pressure against the post or rail is accumulative, and will bring the car to a stop within a short time after the brake shoes are appliecl.

From the foregoing it will be understood that the device is of simple Construction, of few parts which are not liable to get out of order, is strong, durable and eflicient, and can be Conveniently applied to elcvators in use without alterng the general structure o' requiring long stoppage from use.

Various changes in the form or proportions of the parts may be resorted to without departing from the spirit or scope of the invention.

Having thus described the inventiomwhat I desire to secure by Letters Patent and claim is 1. In an emergency brake for elevators, a post or rail, a pair of brake levers provided with brake shoes, a pair of bell-erank levers one of which is provided with a stop lug, links connecting said bell-orank levers, a lever for engaging said lug for holding the brake shoes out of contact with said post or rail, and a spring for applying the brake shoes to said post or rail when released by said lever. r

2. In an emergency brake for elevators, a pair of posts or rails, a pair of brake levers on each side of the elevator car, one of said brake levers being provided with a stop lug, links connecting each pair of said bell-crank levers, a shaft to which two of said brake levers are fixed, a lever for engaging said stop lug, a spring connecting each pair of bell-crank levers, and means for rotating said shaft against the tension of the springs.

3. In an emergency brake, the combination of posts or rails on the sides of the elevator shaft, hangers depending from the floor of the elevator car, a transverse shaft journaled in said hangers, brake levers secured to said shaft, eccentrically disposed brake shoes integral with said levers, one of said levers being provided with a stop lug, a lever for engaging said stop lug, stubshal'ts, coacting brake level-s carried by said stub shafts journaled in said hangers, springs connecting said bell-crank levers, crank arms carried by said transverse shaft and said stub-shafts, a link connecting each pair of said crank-arms and means for rotating said transverse shaft against the tension of said springs.

4. In an emergency brake for elevators, Vertical posts or rails, in combination with two pairs of eccentric brake levers, two pairs of bell-erank levers, one of said bell-crank levers being provided with a stop lug, links connecting each pair of said bell-orank le- Vers, a single transverse shaft carrying two of said bell-crank levers, a brake shoe carried by each of the brake levers, a spring copies of this patent may be obtained for five cents each, by addressing the Commssioner of Patents. Washington, D. C." 

